Background: Originally, cava reconstruction (CR) in liver transplantation meant complete resection and reinsertion of the donor cava. Alternatively, preservation of the recipients inferior vena cava (IVC) with side-to-side anastomosis (known as "piggyback") can be performed. Here, partial clamping maintains blood flow of the IVC, which may improve cardiovascular stability, reduce blood loss and stabilize kidney function. The aim of this study was to compare both techniques with particular focus on kidney function.
Methods: A series of 414 patients who had had adult liver transplantations (2006-2009) were included. Among them, 176 (42.5%) patients had piggyback and 238 had classical CR operation, 112 (27.1%) of the patients underwent CR accompanied with veno-venous bypass (CR-B) and 126 (30.4%) without a bypass. The choice of either technique was based on the surgeons' individual preference. Kidney function [serum creatinine, calculated glomerular filtration rate (GFR), RIFLE stages] was assessed over 14 days.
Results: Lab-MELD scores were significantly higher in CR-B (22.5+/-11.0) than in CR (17.3+/-9.0) and piggyback (18.8+/-10.0) (P=0.008). Unexpectedly, the incidences of arterial stenoses (P=0.045) and biliary leaks (P=0.042) were significantly increased in piggyback. Preoperative serum creatinine levels were the highest in CR-B [1.45+/-1.17 vs 1.25+/-0.85 (piggyback) and 1.13+/-0.60 mg/dL (CR); P=0.033]. Although a worsening of postoperative kidney function was observed among all groups, this was most pronounced in CR-B [creatinine day 14: 1.67+/-1.40 vs 1.35+/-0.96 (piggyback) and 1.45+/-1.03 mg/dL (CR); P=0.102]. Accordingly, the proportion of patients displaying RIFLE stages ≥2 was the highest in CR/CR-B (26%/19%) when compared to piggyback (18%).
Conclusions: Piggyback revealed a shorter warm ischemic time, a reduced blood loss, and a decreased risk of acute kidney failure. Thus, piggyback is a useful technique, which should be applied in standard procedures. When piggyback is unfeasible, cava replacement, which displayed a lower incidence of vascular and biliary complications in our study, remains as a safe alternative.